To Measure Phase Noise - Agilent Technologies 89410A Operator's Manual

Measuring Phase Noise

To measure phase noise

The following procedure demonstrates phase noise measurements using
files on the signals disk that you load into the analyzer's time-capture
buffer. Then, instead of measuring data on the input, we analyze the data
in the capture buffer. Reading data from the capture buffer is not
normally part of measuring phase noise, but is necessary to document the
procedure with simulated measurement data.
The settings that constitute a phase noise measurement:
l
Instrument Mode: PM demodulation
l
Measurement Data: PSD (power spectral density)
l
Data Format: x axis is log scale
l
Averaging, as required
1.
Initialize the analyzer:
Press [ ], [
Instrument Mode
89410A: [
input section (0-10 MHz)
89441A: [
RF section (0-10 MHz)
Press [ ].
Preset
2.
If your analyzer has the optional second input channel installed, turn it off:
channel 2
Press [ ], [
Input
3.
Load the time-capture data into the capture buffer:
Insert the Signals Disk in the analyzer's disk drive.
Press [ ], [
Save/Recall
Press [ ] (bottom softkey), [
Return
Rotate the knob until the file CAPT.DAT is highlighted.
Press [ ], [
recall more recall capture buffer
Using time-captured data causes the analyzer to automatically select the
capture buffer data instead of the input channel and sets the center
frequency, span, and resolution bandwidth to those used when the data
was captured. In a normal phase noise measurement you will set these
parameters instead of loading captured data.
2-2
], then press:
receiver
].
].
], [ ].
ch2 state off
], [ ] to select the internal disk drive.
default disk internal disk
]to display the files on the disk.
catalog on
], [ ] (takes about 2 minutes).
enter